Absorbable block copolymers and surgical articles fabricated therefrom

Abstract

Block copolymers wherein the first block contains from about 20 to about 80 mole percent of repeating units derived from lactide randomly combined with from about 20 to 80 mole percent of repeating units derived from glycolide and the second block contains repeating units derived from lactide and repeating units derived from other bioabsorbable monomeric units, such as glycolide, the second block containing a higher proportion of repeating units derived from lactide than the first block, with units derived from lactide constituting from about 40 to about 90 mole percent of the entire block copolymer are useful in forming surgical articles, including sutures.

What is claimed is:  
     
       1. A block copolymer comprising: 
       (a) a first block containing from about 20 to about 80 mole percent of repeating unites derived from lactide randomly combined with from about 20 to 80 mole percent of repeating units derived from glycolide; and  
       (b) a second block containing of repeating units derived from lactide and repeating unites derived from glycolide, the second block containing about 60 to 100 lactide, the second block having a higher proportion of repeating units derived from lactide than the first block,  
       the units derived from lactide constituting from about 58 to about 90 mole percent of the entire block copolymer.  
     
     
       2. A block copolymer as in claim  1  wherein the the units derived from lactide constitutes about 80 mole percent of the block copolymer. 
     
     
       3. A block copolymer as in claim  1  wherein the first block constitutes from about 30 to about 60 percent by weight of the entire copolymer. 
     
     
       4. A block copolymer as in claim  1  wherein the second block contains from about 60 to 100 mole percent lactide. 
     
     
       5. A block copolymer as in claim  1  wherein the second block contains about 90 mole percent lactide. 
     
     
       6. A block copolymer as in claim  1  wherein the block copolymer is a triblock copolymer. 
     
     
       7. A fiber made from the copolymer of claim  1 . 
     
     
       8. A suture comprising a sterile fiber made from block copolymer having 
       (a) a first block containing from about 20 to about 80 mole percent of repeating units derived from lactide randomly combined with from about 20 to 80 mole percent of repeating units derived from glycolide; and  
       (b) a second block containing of repeating units derived from lactide and repeating units derived from glycolide, the second block containing about 60 to 100 lactide, the second block having a higher proportion of repeating units derived from lactide than the first block,  
       units derived from lactide constituting from about 58 to about 90 mole percent of the entire block copolymer.  
     
     
       9. A suture as in claim  8 , wherein the units derived from lactide constitute about 80 mole percent of the block copolymer. 
     
     
       10. A suture as in claim  8  wherein the first block of the copolymer constitutes from about 10 to about 60 percent by weight of the entire copolymer. 
     
     
       11. A suture as in claim  8  wherein the block copolymer is a triblock copolymer.